Poro hydrolysis

Somewhat similar methods are used in the preparation of bromo-anilines. Consider, for example, the preparation of p-bromoaniline. The action of bromine on aniline gives quantitatively 2, 4, 6-tribro-moaniline. If aniline is first acetylated and then brominated, ortho-and poro-bromoacetanilides are formed with the para isomer predominating. The ortho compound is more soluble in alcohol than the para isomer, and thus can be removed by crystallization. The p-bromoacetanilide is then hydrolyzed. A variation of this method is to add bromine very slowly to aniline dissolved in a large excess of glacial acetic acid, when p-bromoaniline is directly formed, thereby eliminating acylation and hydrolysis. 

Hydrolysis Rote - constant of poro-Nitrophenyl Acetate versus [j8-Cyclodextrin]... 

On the basis of a series of comprehensive studies, it is found that the key point of this novel synthesis process is the very high rate at which the hydrolyzed metal alkoxides undergo condensation reactions in aqueous solution. A poro-gen mechanism has been proposed to explain the formation of porous hierarchy via the spontaneous self-formation phenomenon [124,139]. The alcohol molecules released suddenly during the hydrolysis and condensation reactions can be considered as porogens in the generation of the funnel-like macrochannels with hierarchically mesostructured porous walls. 

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